Carton



May 5 R936. A. s. HEINYEMAN 2,39,315

CARTON Filed Jan. 9, 1935 Patented May 5, 1936 UNITED STATES PATENT or ies Application January 3 Claims.

This invention relates to containers or cartons constructed of paper or cardboard and has to do particularly with the construction of small cartons of rectangular or trapezoidal shape, such as those adapted to contain small quantities of butter and the like.

An object of the invention is to provide a carton that may be folded from a single blank and that, when formed, is self-locking so that it retains its shape without the necessity of being glued.

Other more specific objects and features of the invention will become apparent from the following detailed description which refers to the drawing.

In the drawing:

Fig. 1 is a perspective view of a carton in accordance with the invention in partially folded condition;

Fig. 2 is a perspective view of the carton completely formed but with the cover portion broken away; and

Fig. 3 is a plan view of the blank from which the carton is formed.

Referring first to Fig. 3, the blank from which I form my carton is preferably constructed of heavy paper or thin cardboard which may be waxed or otherwise treated, if desired, to render it waterproof or resistant to other substances. This blank comprises a bottom portion I, two side portions 2 and 3, respectively, which are joined to the bottom portion I, a pair of inner end portions 4 and 5, respectively, which are joined onto the ends of the side wall portion 2, a pair of inner end portions 6 and I, respectively, which are joined onto opposite ends of the side wall portion 3, a pair of outer end wall portions 8 and 9, respectively, which extend from the outer ends of the bottom wall portion I, and a cover portion II] which extends from the side portion 3. The outer end portions 8 and 9 have flaps I I and I2 thereon which are adapted to be folded inwardly along the dotted lines I3 and which are provided with slots I 4. The inner end wall portions 4, 5, 6, and I, respectively, each have a notch I5 therein which leaves a tab 20 having at one edge a projecting or overhanging shoulder I6 for a purpose to be described later.

The cover portion III is provided with end flaps I7 and I8, and a side flap I9. It is to be understood that in forming the carton the blank shown in Fig. 3 is folded along the dotted lines.

Thus the operation of folding the blank is, performed as follows: First the side wall portions 2 and 3, respectively, are folded upwardly with re- 9, 1935, Serial No. 958

spect to the base portion I and the inner end wall portions 4, 5, 6, and I are folded inwardly at right angles to the side wall portions. The side wall portions 2 and 3 are then squeezed together so that the inner end wall portions 4 and 6 overlap each other and the inner end wall portions 5 and I also overlap each other, as shown in Fig. 1.

While the side walls are squeezed inwardly, as shown in Fig. 1, the outer end wall portions 8 and 9, respectively, are then folded up alongside of the inner end wall portions 4, 6 and 5, 1, respectively, and the flaps I2 and I3 folded inwardly, the overlapping tabs 20 on the inner end wall portions projecting through the slots I4. Thereafter the side wall portions 2 and 3 are spread apart to bring the edges of the inner end wall portions 4, 6 and 5, I, respectively, in abutting relation with each other instead of overlapping relation, as shown in Fig. 1. This final condition is shown in Fig. 2. The length of the slots I4 is made equal to the width of the base portions of the two tabs 20 on the adjacent inner end wall portions so that when the carton has been assembled as shown in Fig. 2 the tabs 20 fit snugly within the slot I4, thereby preventing release of the flap II.

The corners of the flaps II and I2 are preferably tapered as shown at 2| to permit ready folding of the tabs. Thus as a result of their tapered construction each of the tabs II and I2 can be entered between the side wall portions 2 and 3 (referring to Fig. 1) even when the latter are compressed together to cause the inner end wall portions to overlap. However, as each of the flaps I I and I2 is forced downwardly between the side walls 2 and 3, it tends to separate them into the normal position shown in Fig. 2, in which the inner end wall portions 4 and 6 move from overlapping relation into abutting relation.

The carton, as disclosed in Fig. 2, is ready to be filled and after being filled is closed by merely folding down the cover portion 2, the end flaps I1 and I8 and the side flap I 9 being adapted to slide within the side and end wall portions of the finished carton.

The particular novel feature of my carton is the construction of the end wall portions involving the members 4, 6, 8 and I4 and their method of assembling. Obviously this construction may be employed in other cartons in addition to the specific form of carton disclosed. The invention, therefore, is to be limited only as set forth in the appended claims.

I claim:

1. A carton formed from a single blank and comprising: a bottom or base portion; a pair of side Wall portions continuous with and folded up from said base portion; a pair of inner end wall portions each extending half way across the end of the carton in abutting relation with each other and each being a continuation of and being folded in from one of said side wall portions and having a notched tab extending above its upper edge; an outer end wall portion continuous with and folded up from said base portion and having a flap at its upper edge folded inwardly and downwardly over the upper edges of said inner end wall portion and having a slot for receiving said notched tabs on said inner end wall portion, said slot being substantially equal in length to the combined width of said two tabs at the base of the latter, and the tabs being wider at their upper ends than at their bases whereby said tabs are locked in said slot when said inner end wall members are in abutting relation.

2. A carton as described in claim 1, in which the lateral edges of the flap on said outer end wall portion are tapered inwardly at the ends whereby the end of said flap may be inserted between said side wall portions (during the forming process) while the side walls are squeezed together at their upper edges to cause said inner end wall portions attached thereto to overlap.

3. The method of folding a carton from a blank having: a bottom or base portion; a pair of side wall portions continuous with said base portion; a pair of inner end wall portions each adapted to extend half way across the end of the completed carton, and each being a continuation of one of said side wall portions and having a notched tab extending above its upper edge; and an outer end wall portion continuous with said base portion and having a flap at its outer edge adapted to be folded inwardly and downwardly over the upper edges of said inner end Wall portions and having a slot for receiving said notched tabs on said inner end wall portions, which slot is substantially equal in length to twice the width of one of said tabs at the base of the latter, said tabs being wider at their upper ends than at their bases; which method comprises folding said inner end wall portions at right angles to said side wall portions, folding said side wall portions relative to said base portion, over-squeezing said side wall portions to cause said inner end wall portions to overlap, folding said outer end wall portion against said inner end wall portions, then folding said flap on said outer end wall portion over said inner end wall portions while the latter are in overlapped relation, said tabs projecting through said slot in said flap, and then separating said side wall portions into normal position, thereby shifting said inner end wall portions from overlapping to abutting position and spreading said tabs to fill said slot.

ARTHUR S. HEINEMAN. 

